Honey is one of the oldest foods known to man, being eaten both for its palatability and its nutritive value. As a food ingredient, honey has fine flavor and the image of old fashioned goodness. Honey does have some negative attributes associated with its use. The two major criticisms of honey are handling problems and its natural affinity to return to a crystallized state.
In its natural form, honey is a viscous, sticky, adhesive fluid which can be slowly poured and/or spread onto a surface and which continues to flow after it has been applied to a surface. Honey is difficult to pour or spoon due to its adhesiveness and stickiness. Honey can be heat processed to delay granulation for 6 to 18 months but eventually some coarse crystals will accumulate. The extent of this granulation is known to be related to glucose (dextrose hydrate) supersaturation.
Honey can be described as the nectar and saccharine exudations of plants, gathered, modified and stored in the comb by honey bees. Through a combination of evaporation and sucrose inversion, the nectar, which contains about 60%-80% water, is concentrated to about 17-18% water. At the same time, enzymes in the honey stomach of the bee convert a majority of the sucrose in the nectar to fructose and glucose. Comb honey is honey still retained in the cells of the comb. Processed honey is honey separated from the comb; either extracted from the uncrushed comb by gravity or centrifugal force or strained from crushed comb.
Honey differs widely in its chemical composition depending on the plant source and on the bee which converts the nectar to honey. The range of honey components and their average values are listed in table I.
TABLE I ______________________________________ Components Range (%) Average (%) ______________________________________ Water 13-23 17 Fructose 23-44 38 Glucose (Dextrose) 22-41 31 Sucrose 0.2-8 1.3 Other Sugars 3-24 9 pH 3.8-4.2 4 ______________________________________
Pectin is a complex polysaccharide (principally D-galacturonic acid) with a molecular weight in the range of 60,000 to 150,000, depending on the plant source. The polyglacturonic acid is partially esterified with methoxyl groups. The ratio of methoxylated galacturonic acid groups to total galacturonic acid groups is termed the "degree of methoxylation" (DM). Commercial pectins are divided into two main groups - high-methoxyl (HM) pectins and low-methoxyl (LM) pectins. Typically, the HM pectins have a DM range of 60-75%, while LM pectins have a DM range of 25-45%.
Pectin is a commonly used gelling agent for carbohydrate solutions. High-methoxyl pectin will gel sugar solutions containing 55-70% or more sugar, but require a pH of about 3.4 or below. It has been suggested that the gelling action of pectin occurs from physical or chemical changes that decrease the solubility of the pectin, resulting in local crystallization. For high-methoxyl pectins, the required changes are brought about by the addition of sugar and hydrogen ions. Addition of alkaline metal earth cations, usually calcium, is sufficient to induce the gelation of low-methoxyl pectins.
High-methoxyl pectin gels are plastic, have high elasticity and have good flavor release. These pectins will gel sugar solutions having a minimum of 55% soluble solids within a pH range of 2.0 to 3.4. In general it is necessary to adjust the pH below 3.5 to achieve proper gelation with high-methoxyl pectins.
Low-methoxyl pectin gels vary in texture with calcium ion concentration and solids. At low calcium concentrations, soft, coherent gels are formed. At high calcium concentrations, gels are hard and brittle. These pectins are less dependent than high-methoxyl pectins on sugar content and pH to form proper gels.
A number of experimentors have attempted to utilize the gelling properties of pectin in honey containing compositions.
Hoshino, in Japanese publication No. Sho47/1972-15, Jan. 15, 1972, describes a honey and butter composition which gels upon the addition of pectin and so retains its shape instead of flowing. Hoshino adds either a high-methoxyl pectin, in quantities of 0.5% or more, in conjunction with small quantities of acid, or a low-methoxyl pectin which has been treated and which is combined with alkaline earth metals.
Shimizu, in Japanese publication No. Sho53/1978-81665, July 19, 1978, describes a fruit jelly and honey composition which is mixed with 1.4% to 2.0% pectin and citric acid and the pH adjusted to 3.1.+-.0.5. This composition does not require a preservative and does not form a surface film.
Shimizu, in Japanese publication No. Sho55/1980-1165760, Dec. 24, 1980, describes a crystalline honey composition and a method of artificially crystallizing honey. Shimizu adds low-methoxyl pectin to honey, then adds a calcium salt solution as a nucleus for the crystallization of the honey. The gelled honey product is stablized by the pectin.
White, U.S. Pat. No. 2,902,370, Sept. 1, 1959, uses pectin to coat honeycomb in a comb honey product, to prevent the honeycomb from serving as a nucleation site for granulation.
Bryan, U.S. Pat. No. 3,851,067, Nov. 25, 1974, uses pectin gels and honey to coat citrus halves.
Arden, U.S. Pat. No. 4,021,583, uses honey and pectin in a fruit flavored frozen confection.
These references do not however, describe a method for producing a semi-gelled honey product which maintains all the desirable characteristics of honey, i.e. flavor, color and sweetness, while at the same time having improved textural qualities which enable it to be spread easily and which prevent crystallization. There is a continuing need for a spreadable honey with good keeping properties.
The present invention overcomes the difficulties experienced by the compositions of the prior art, maintaining all the desirable organoleptic characteristics of honey, while at the same time making it easy to handle and spread and increasing its shelf life.